Die Ringvorlesung Informatik wendet sich an DissertantInnen, an angehende DissertantInnen (derzeit DiplomandInnen), an alle interessierte MitarbeiterInnen der Forschungsgruppen der Informatik und Informationstechnik sowie allgemein an aktueller Informatik-Forschung interessierte Personen.

In sechs Vorträgen werden Vertreter der Informatik und Informationstechnik (Bouchachia, Fliedl, Kop, Rinner, Schartner, Zanker) ausgewählte aktuelle Forschungsarbeiten vorstellen und mit den DoktorandInnen vertiefen.

Spezielle Ziele dieser Lehrveranstaltung sind:

• Die HörerInnen sollen durch die Vorträge Ein- und Überblicke zu aktuellen Forschungsfragen, -methoden und -projekten in der Informatik und Informationstechnik erhalten.
• Die DissertantInnen sollen ihren Standort in ihrem eigenen Dissertationsvorhaben bestimmen, d.h. sich ihr(e) Forschungsgebiet, -fragen, -ziele und -methoden klar machen und konzis dokumentieren.
• Die DissertantInnen sollen Querbezüge zu einem der in den Vorträgen dargestellten „fremden“ Forschungsgebiete identifizieren, Anknüpfungspunkte und möglichen Nutzen herausarbeiten, Kontakt zu dem entsprechenden Vortragenden herstellen, die Querbezüge mit ihm diskutieren und in Form der Bearbeitung eines kleinen „Projekts“ vertiefen.
• Die DissertantInnen sollen all dies (Dissertationsvorhaben, Standort, Querbezüge und möglicher Nutzen, „Projekte“ und Ergebnisse bzw. Erkenntnisse daraus) abschließend den anderen DissertantInnen und den Vortragenden präsentieren und mit ihnen darüber diskutieren.
• Damit sollen letztlich die beteiligten Forschungsgruppen einander besser kennenlernen, die Kontakte intensiviert, Querbezüge identifiziert und mögliche Kooperationen initiiert werden können. Die DissertantInnen sollen erkennen, ob/dass sie in anderen Forschungsgruppen Unterstützung bekommen können.

Themen

• 30.03.2011 Hellwagner: Vorbesprechung
• 06.04.2011 Rinner: „Einführung in Sensornetze„
• 13.04.2011 Fliedl: „Text Engineering – A Challenge for Computational Linguistics„
• 04.05.2011 Schartner: „Schlüsselaspekte des Keymanagement„
• 11.05.2011 Bouchachia: „Intelligent Living Environments: A Concise Introduction„
• 25.05.2011 Kop: „Domänenmodellierung – Ein Ansatz und seine linguistischen Aspekte„
• 01.06.2011 Zanker: „Ways towards optimizing recommender systems„

Ich möchte gerne an meinen ersten Bericht vom August anknöpfen und euch Neuigkeiten von meinem Praktikum in den USA berichten. Mittlerweile arbeite ich nun schon fast 4 Monate in den Dolby Laboratories in Los Angeles. Das Praktikum läuft bis jetzt sehr gut und die Kollegen sind wirklich sehr nett und hilfsbereit. Ich habe meine Arbeitszeit damit verbracht die Adobe Produkte für Videostreaming, Playback und Enhancement auf Desktopsystemen und Android Smartphones zu untersuchen. Dabei habe ich mich speziell mit Streamingmethoden wie dynamisches HTTP Streaming  und Video Processing am Client auseinandergesetzt. Alle Details kann ich aber leider nicht verraten 😉

Zur Performanceverbesserung bin ich nun am Android-Smartphone-Client von den Adobe Produkten (u.a. Flash Player) auf native C Anwendungen umgestiegen. Hierzu verwende ich eine, für den ARM Prozessor optimierte Version von FFMPEG und untersuche die Möglichkeiten der mobilen GPU mittels OpenGL ES. Da sich mein Praktikum nun schon langsam aber doch auch dem Ende nähert konzentriere ich mich auch darauf eine Demo-Anwendung meiner Ergebnisse für das neue Samsung Galaxy Tablet zu programmieren und diese dann vor meiner Abteilung bei Dolby zu präsentieren und eventuell eine Paper für eine Konferenz darüber zu schreiben.

Natürlich habe ich meine Freizeit exzessiv genützt um mir das Land anzusehen. Nach meinem „Roadtrip“ nach Las Vegas und San Francisco vor Beginn des Praktikums habe ich nun auch den Grand Canyon und San Diego besucht. Ich hatte zwar schon viele sehr positive Gerüchte über San Diego gehört, aber die Stadt hat alle meine Erwartungen übertroffen.

Auch von der sportlichen Seite Amerikas habe ich mir einiges angesehen: Mit meinen Kollegen von Dolby habe ich ein Basketballspiel der L.A. Lakers im berühmten Staples Center besucht  und wie es sich für einen Eishockey-Fan gehört habe ich mir natürlich auch ein NHL Eishockeyspiel angeschaut: L.A. Kings vs. Tampa Bay Lightnings. Auch das Baseball-Spiel L.A. Dogders gegen Colorado Rockies habe ich mir angesehen und war begeistert von der Stimmung im Stadion.

Zwischenzeitlich hat mir Dolby auch die Möglichkeit gegeben die Adobe MAX Konferenz in Los Angeles zu besuchen. Das ist sozusagen die „Hausmesse“ von Adobe auf der sie ihre Produkte vorstellen, neuste Entwicklungen zeigen und sehr viele Expertenvorträge anbieten (ca. 10.000 Besucher). Zusammen mit einem Mitarbeiter meines Teams in dem ich bei Dolby arbeite war ich dort für 3 Tage und besuchte viele Vorträge im Bereich von Video Streaming und Decoding mittels Adobe Produkten wie Flash und AIR. Eines der Ziele warum mich Dolby auf die Konferenz geschickt hat war auch dass ich mich mit Adobe Entwicklern über Möglichkeiten, Probleme und Performanceoptimierungen sprechen konnte. Als positive Überraschung habe ich bei dieser Konferenz ein Android Smartphone von Motorola und eine Google TV Box geschenkt bekommen. Ein weiteres Highlight der Konferenz war die Keynote des Adobe CTO Kevin Lynch und der Special Guest William Shatner (Captain Kirk aus Raumschiff Enterprise), was mich als Science Fiction Fan natürlich besonders freute.

Wie ich schon in meinem letzten Bericht erwähnte kann ich es nur jedem Empfehlen die Zeit während des Studiums zu nutzen und entweder ein Praxissemester oder ein Semester auf einer Uni im Ausland zu machen. Lasst euch nicht vom organisatorischen Aufwand abschrecken, die Arbeit ist es am Ende auf alle Fälle wert.

Schöne Grüße aus dem sonnigen Kalifornien!

Stefan Lederer

Abstract:

Starting with the consideration that massive multiplayer online gaming (MMOG) is a latency-critical representative of the class of highly interactive multi-user multimedia applications, we have acquired trace data from an MMOG operator and investigated the features of this traffic. Approaching latency from several angles, we found two quite different improvements that can improve a variety of interactive applications.

The first is based on the understanding that reliable transport protocols such as TCP and SCTP are basically suited for a class of interactive traffic that generates thin streams, but that some modifications are required. These thin-stream modifications work nicely with regular applications and unmodified receivers, but produce easily noticable improvements for thin-stream applications such as games, remote login, voice-over-IP, and the like.

The second is based on an observation that games and many other distributed virtual environments are divided in areas-of-interest, and that avatars‘ locations in such areas define frequently changing all-to-all overlay multicast groups. Considering that IP multicast is not generally available, we have investigated how such multicast groups within a larger distributed application should be maintained and updated. Depending on application parameters, the appropriate decisions differ quite widely, and we have explored a large part of the parameter space.

Biographie:

Carsten Griwodz leads the Media Performance Group at the Norwegian research company Simula Research Laboratory AS, Norway, and is Professor at the University of Oslo. He received his Diploma in Computer Science from the University of Paderborn, Germany, in 1993. From 1993 to 1997, he worked at the IBM European Networking Center in Heidelberg, Germany. In 1997 he joined the Multimedia Communications Lab at Darmstadt University of Technology, Germany, where he obtained his doctoral degree in 2000. His interests lie in the improvement of system support for interactive distributed multimedia, with heterogeneous parallel processing, operating systems and protocol support for streaming applications and multiplayer games in particular. He leads the StorIKT project Verdione that investigates system support for the World Opera, and is member of the Center for Research-based Innovation „Information Access Disruptions“ that develops next generation search technology.

Abstract:

Adaptation of multimedia content is a topic that has been addressed from many points of view, namely from an elementary media perspective. Rich Media content is a particular type of multimedia content, i.e., a collection of elementary media, but with a strong emphasis on compositing aspects and on dynamic and interactive behaviors. Adaptation of Rich Media content is hence quite a different problem from elementary media adaptation. This problem has been tackled in the past, but global, accepted approaches have not yet been widely adopted. This talk will first survey the state-of-the-art approaches in Rich Media adaptation, including the scalable approach developed in our lab. The talk will also present the research challenges remaining ahead.

Cyril Concolato is Associate Professor in the Multimedia Group at Telecom ParisTech, Paris, France, where he received his master and doctoral degree in Computer Science in 2000 and 2007, respectively. His interests lie in multimedia scene descriptions and in interactive multimedia applications. He is the author or co-author of 8 journal papers and 29 conference papers. He is an active participant to the standardization bodies of MPEG and W3C. Finally, he is one of the project leaders of the Open Source project GPAC.

Homepage of Cyril Concolato: http://concolato.wp.institut-telecom.fr/

András Lörincz short bio: professor, senior researcher has been teaching at the Faculty of Informatics at Eötvös University, Budapest since 1998. His research focuses on distributed intelligent systems and their applications in neurobiological and cognitive modeling, as well as medicine. He has founded the Neural Information Processing Group of Eötvös University and he directs a multidisciplinary team of mathematicians, programmers, computer scientists and physicists. He has acted as the PI of several successful international projects in collaboration with Panasonic, Honda Future Technology Research and the Information Directorate of the US Air Force in the fields of hardware-software co-synthesis, image processing and human-computer collaboration. He authored about 200 peer reviewed scientific publications. He has received the Széchenyi Professor Award, Master Professor Award and the Széchenyi István Award in 2000, 2001, and 2004, respectively. In 20

04, he was awarded the Kalmár Prize of the John von Neumann Computer Society of Hungary. He has become an elected Fellow of the European Coordinating Committee for Artificial Intelligence for his pioneering work in the field of artificial intelligence in 2006.

Abstract: In recent years, a number of novel applications have emerged through „L1 Magic“, the intriguing property that cost functions using l0 norm (i.e., the minimization of the number of the elements of a basis set representing a given input) and cost functions using l1 norm are equivalent under certain conditions. This feature turns relevant NP-hard-looking problems to polynomial ones. Based on this and related recent advances in signal processing, we study a novel model in which signal is decomposed into a dense signal of low intrinsic dimension and into a sparse signal. In contrast to other approaches, this preprocessing in conjunction with efficient sparse coding can achieve structural sparseness thus allowing for the formation of highly overcomplete and highly sparse, but combinatorial dictionaries. We shall present some results for natural images and will discuss the advantages of the separation of the two types of representations for other data, including movies and texts.

A key requirement in packet switching networks is an efficient way to access information stored within the routers. The most obvious example is the routing table and its associated forwarding information, accessed at least once for each packet traversing the router, but advanced protocols may require to store and access flow state information too, adding scalability problems as well. In this seminar, an innovative, highly efficient way to exploit the cooperation between end nodes and intermediate systems will be presented. It is based on Distributed Linked Data Structures (DLDS), an extension of the classical linked data structures where pointers are stored in data packets, travel along the route from sender to receiver and address memory locations within the routers belonging to the path. When integrated in network protocols (for example as a new IP option field), DLDS provide the router the memory addresses needed to access the required information without the need of searching. This leads to constant cost procedures, increasing performance and overcoming scalability problems. DLDS may support several different applications; two of them will be discussed in detail: resource reservation for deterministic Quality of Service support (based on an algorithm called REBOOK) and routing tables lookup.

Pier Luca Montessoro was born in Torino, Italy, on November 25, 1961. He received the Dr. Eng. degree cum laude in Electronic Engineering from the Politecnico di Torino, Italy, in 1986. He has been with the Consiglio Nazionale delle Ricerche (C.N.R.), the Italian National Council for Scientific Research, from 1988 to 1992. During this period he has also been scientific consultant for the Digital Equipment Corporation (later Compaq) in Hudson, Mass. (USA) in the field of simulation for VLSI design. His teaching and research activities began at Politecnico di Torino where he taught computer programming, computer architectures, computer networks and databases in a Management Engineering course from 1990 to 1994. In November 1992 he moved to University of Udine as associate professor in computer science and since Novembre 2002 he is full professor. His teaching activity at the engineering faculty is on computer science fundamentals and computer networks. He recorded two video-courses for the Nettuno on-line university, he is author of several didactic publications, more than sixty scientific papers, some patents and together with Silvano Gai and Pietro Nicoletti wrote a popular book („Reti locali: dal cablaggio all’internetworking“, SSGRR, in italian) on structured cabling systems, LAN and internetworking, also included in their multimedia CD-ROM. His research interests, after several years spent on CAD for digital circuits design and, later, on multimedia systems for teleteaching and e-learning, are currently focused on computer networks and network security and on pervasive computing. From 2003 to 2009 Pier Luca Montessoro has been head of the Electrical, Management and Mechanical Engineering Department and from 1995 to 2002 director of the Computer Center of the University of Udine. He has been member of the NCGT of the CRUI („Conferenza dei Rettori delle Università Italiane“) for the GARR computer network, the italian research network, president of master course in Multimedia Sciences and Technologies of the University of Udine, rector’s delegate for the computer networks and telematic systems of the University of Udine, member of the Tecnical Board („Comitato Tecnico“) of the CINECA consortium; He is currently representative of University of Udine in several national committees. Related to the interest in multimedia systems, Pier Luca Montessoro developed some studies about musical piracy and has been consultant of magistrates in several proceedings. He is also member of SIAE („Società Italiana degli Autori ed Editori“), the italian authors and editors society, as composer and song writer.

In der Vortragsreihe des Projektes Informatik verstehen hat am 8. Juni Herr Prof. Böszörmenyi vom Institut für Informationstechnologie über das Thema „Die unsichtbaren Diener – Der Compiler und seine Artgenossen“ referiert. Neben Mitarbeitern der Universität nahmen erfreulicherweise auch Lehrer und zahlreiche Schüler am Vortrag teil.

Link zu den Vortragsfolien: http://www.itec.uni-klu.ac.at/~laszlo/courses/cb/Compiler.pdf